Fabric roll take-up for knitting machines



Feb. 19, 1952 R. H. LAWSON 2,586,470

FABRIC ROLL TAKE-UP FOR KNITTING MACHINES Filed June 6, 1947 2 SHEETSSHEET l INVENTOR ROBERT H. LAWSON 6 2221s wiiarneys Feb. 19, 1952 R. H. LAWSON 2,586,470 FABRIOROLL TAKE-UP FOR KNITTING MACHINES Filed June 6, 1947 2 SHEETSSHEET 2 INVENTOR ROBERT- H. LAWSON 3y 71,119 @Z 20 rney-s creasing tension of the fabric.

Patented Feb. 19, 1952 FICE FABRIC ROLL TAKE-UP FOR KNITTING MACHINES Robert H. Lawson, Laconia, N. H., assignor to Scott & Williams; Incorporated, Lacom'a, N. H., a corporation of Massachusetts Application June 6, 1947, Serial No. 753,091

13 Claims. 1

This invention relates to a fabric roll takeup for a knitting machine. The invention is especially useful in connection with underwear knitting machines.

In knitting machines making continuous fabrics, it is generally necessary to wind such fabrics into rolls of suitable length. It is important to wind the fabric under substantially uniform light tension. It is also important to avoid sud- .den jerks on the fabric which result in its being under different degrees of tension in different parts of the roll. Heretofore better grades of knitted fabrics have been allowed to drop into a box under the takeup so as not to be distorted.

I have found that rolls of knitted fabric may be wound under uniform tension by rotating the shaft upon which the fabric is wound at a rate which is slower than, but dependent upon, the tension of the knitted fabric beingrolled. To this end, there is provided means responsive to .the tension of the knitted fabric being rolled, whereby the fabric is rolled more rapidly under diminishing tension and less rapidly under in- My invention is characterized by a lever system governed by the tension of the fabric as it approaches the roll, and a clutch operated by the lever system for connecting the power to the shaft upon whichthe fabric is wound. The clutch includes a planetary reduction gear train whereby the pow- Ier is applied to the shaft at reduced speed and increased force. This clutch changes the speed of the fabric wind-up without jumps or jerks, to maintain the required uniform light tension. The speed reduction gear train and its hunting tooth and the clutch cause the roll to assume a speed just sufficient to roll the fabric up at a constant rate as it is knitted. They also limit the maximum speed of the shaft. The effect of the parts is to produce a gradual adjustment of the takeup.

The invention is shown by way of illustration in its application to an underwear kniting ma- Zparatus illustrated in Fig. 1;

Fig. 3 is a perspective view of the shaft-rotating clutch employed in the apparatus, with parts thereof brokenaway to show the internal construction;

4 is an elevation of the clutch-engaging 2 elements as illustrated in Fig. 3, with the clutch disengaged; and

Fig. 5 is an elevation similar to that shown in Fig. 4 with the clutch engaged.

In the embodiment of the invention which is illustrated in the drawings, there is'shown the base l0 and the front legs II and I2 of an underwear knitting machine. The knitted fabric [3 extends downwardly through the base 0 to a pair of the usual fabric takeup rolls l4 and I5, between which it passes. Continuing thence, the fabric passes upwardly and over a feeler bar l6 controlling the rate at which the fabric is wound upon the roll in a manner later to be described. From the feeler bar, the fabric moves downwardly and is wound into a roll I! upon a shaft I8 which is carried by the two front legs II and I2 of the knitting machine. The shaft is turned by a constantly-driven pulley I9 which is rotated by a belt 20 operated from the main part of the knitting machine.

The shaft I8 is turned by the pulley H! at a rate which is dependent upon the tension of the knitted fabric which is being rolled thereon. To this end, a friction clutch 2| engages the constantly-driven pulley IS with the shaft l8 in response to the tension of the knitted fabric as it passes over the feeler bar l6. Thus, with increasing tension on the fabric, the friction clutch is progressively released so that the shaft l8 rotates more slowly, whereas with decreasing tension on the fabric being rolled, the friction clutch is progressively engaged so that the shaft 18 rotates more rapidly.

The friction clutch 2| is controlled by a clutch lever 22 which is operated by a lever system including the feeler bar l6 over which the knitted fabric passes. Accordingly, the feeler bar I6 is mounted upon the machine in such manner that tension on the fabric passing over it depresses the feeler bar, whereasrelease of such tension permits the feeler bar to rise. In the embodiment here shown, a lever 23 is pivoted as at 24 to a lug 25 fixed beneath the base ID of the knitting machine. The feeler bar It is carried by the lever 23, one end of which is attached thereto as at 26. The other end of the feeler bar is rigidly fixed to a second lever 21 which is pivoted as at 28 to a downwardly extendinglug 29 fixed to the Thus, increasing tension of the knitted fabric l3 passing over the feeler bar tends to move the pivoted levers 23 and 21 in a clockwise direction about their pivots 24 and 28, as viewed in the drawings. Diminishing tension of the knitted fabric passing over the feeler bar permits the counterweight 3| to turn the pivoted levers 23 and 21 in a contra-clockwise direction, as viewed in the drawings. The lever system is therefore responsive to the tension of the fabric being rolled.

Movement of the lever system is employed to govern the friction clutch 21. As here shown, a link 32 is pivoted to the lever 23 between its pivot 24 and the point 26 at which the feeler bar 16 is attached. The link 32 is pivoted at its other end to the outer end of the clutch lever 22. Consequently with increasing tension on the knitted fabric, the lever 23 applies pressure to the link 32, thereby turning the clutch lever 22 in a clockwise direction, as viewed in the drawings. Conversely, decreasing tension on the knitted fabric permits the counterweight 3| to move the lever 23 in a contra-clockwise direction, thereby applying tension to the link 32 and moving the clutch lever in a contraclockwise direction, as viewed in the drawings. Since it is desired to roll the fabric more rapidly as the tension thereon diminishes and less rapidly as the tension thereon increases, the friction clutch is so connected that movement of the clutch lever in a clockwise direction progressively releases the clutch and movement of the clutch lever in a contra-clockwise direction progressively moves the clutch toward full engagement. Thus, the rate at which the fabric is rolled upon the shaft I8 is controlled by the tension of the fabric as it passes over the feeler bar 16.

Various types of friction clutch may be employed for driving the shaft Hi from the pulley l9. A preferred form of clutch is illustrated in Figs 3, 4 and 5. In this clutch, a hunting tooth planetary gear train is employed to drive the shaft from the pulley with reduced speed and increased force. The pulley may therefore be driven at a rapid rate, and the friction clutch will cause the shaft to be rotated slowly and with considerable force. In the illustrated embodiment, a driving gear 33 is keyed or otherwise fixed to the shaft 18 concentrically therewith. The pulley i9 is mounted for free rotation upon the shaft l8, as on ball bearings 34, beyond the driving gear 33. A planetary gear 35 is journaled on pulley IQ for free rotation between the hub and the rim of the pulley and in mesh with the driving gear 33. Thus, as the pulley rotates about the shaft, the unrestrained planetary gear 35 merely idles about the driving gear without turning it.

By restraining rotation of the planetary gear 35 as the pulley 19 is driven, the driving gear 33 may be driven by the pulley. The clutch lever 22 operates means for restraining rotation of the planetary gear. Accordingly, an idler plate 36 is mounted on the shaft l8 for free rotation thereon, and an idler gear 31 is concentrically connected to the idler plate for rotation therewith upon the shaft. The idler gear is positioned next to the driving gear 33 and also meshes with the planetary gear 35, the face of which has sufficient width to engage both the driving gear and the idler gear. The idler gear has a greater number of teeth, preferably one more, than the driving gear, for a reason which will presently appear. This idler gear 31 may also be identified as the hunting tooth gear.

When the idler plate and idler gear are not restrained, they float freely upon the shaft l8 and do not affect the shaft or the pulley 19. As the pulley 19 carries the planetary gear 35 around the completely restrained, or stationary, idler gear, however, the teeth of the planetary gear successively mesh with the teeth of the stationary idler gear. The planetary gear always rotates. Its rotation upon its own axis may be varied by freeing, on the one hand, or constraining, or even stopping, gear 3?, on the other hand, so as to rotate the driving or sun gear 33. However, the variation in rotation of planetary gear 35 on its own axis is very slight and its rotation about shaft I8 does not vary. Assuming the three gears have a number of teeth corresponding to their identifying numbers, except for gear 31, for which we will assume 34 teeth, then for each revolution of pulley [3 gear 35 will travel 33/35 revolutions about its own axis when shaft 18 is not turning and will travel 34/ 35 revolutions about its axis when shaft I8 is turning at its maximum speed which is the condition when gear 31 is held stationary. It is also to be noted that the rate at which the planetary gear rotates is dependent upon the number of teeth on the idler gear. The teeth of the planetary gear mesh at the same time with the teeth of the driving gear 33 fixed to the shaft [8. Since there are a greater number of teeth on the idler gear than on the driving gear, it follows that the planetary gear necessarily advances the driving gear as it foliows the stationary idler gear. Furthermore, the rate at which the planetary gear advances the driving gear during each revolution about the idler gear is equal to the difference between the number of teeth on the idler gear and the number of teeth on the driving gear.

If the idler gear is not held stationary by the friction clutch but merely has its rate of rotation reduced, it will be clear that the driving or sun gear 33 will not rotate as rapidly during each revolution of the pulley as it would if the idler gear were held in fixed position. Some idling will occur. The rate at which the drivin gear, and the shaft fixed to it, will then be rotated will be less than their rate of rotation with the idler gear held stationary.

In order to hold the idler plate 36, and with it the idler gear 31, in a stationary position, or to restrain them less fully, coacting friction means is provided which may be operated by the clutch lever 22. In the present embodiment, this friction means includes a circumferential flange 38 upon the idler plate 36, and a plate 39 fixed to the frame of the knitting machine having a circumferential flange 40 thereon surrounding the fiange 38 of the idler plate 36. A brake band 4! has one end fixed to the flange 40 of the fixed plate 39 and extends between the circumferential flanges 38 and 40 to the clutch lever 22 where its other end is fixed. The clutch lever 22 is pivoted, preferably as at 42, to the fixed plate 39. Thus, as the clutch lever is moved in a contra-clockwise direction, as viewed in the drawings, the brake band 41 is tightened about the flange 38, thereby restraining or holding stationary the idler plate 36 and the idler gear 31 and causing the pulley 19, through the planetary gear 35 and the driving gear 33, to turn the shaft 18. Movement of the clutch lever in the opposite direction releases the brake band and permits the idler plate and idler gear to fioat freely upon the shaft 18.

From the foregoing, it will be clear that increased tension of the fabric l3 passing over the feeler bar l6 causes the link 32 to lower the clutch lever 22 or to move it in a clockwise direction, as viewed in the drawings. This loosens the friction clutch 2i and causes the shaft i8 to roll up the fabric thereon with decreasing speed and force as the clutch lever is moved further in the direction indicated. Conversely, release of tension on the fabric passing over the feeler bar [6 permits the counterweight 3! to move the link 32 in an upwardly direction, thereby turning the clutch lever 22 in a contra-clockwise direction and progressively tightening the brake band 4| to restrain the idler plate 38 and the idler gear 31, whereby the pulley l9 turns the shaft [8 more rapidly and with greater force. It is to be observed that tightening or loosening of the brake band is gradual, and that the response of the planetary gear system is progressive. Thus the epicyclic gear train makes it possible for the speed of the shaft to gradually slow down to synchronism with the knitting as the rolling up of the fabric catches up with the knitting. There is no sudden throwing in and out of a clutch, with resulting jumps and jerks which distort the fabric.

Thus, means is provided for rotating a shaft, upon which fabric from a knitting machine is rolled up, in response to the tension of the knitted fabric being rolled thereon, to maintain a steady uniform tension in the roll. The apparatus is simple, rugged, easily accessible for adjustment and repair, and is positioned externally of the machine where it will not interfere with other moving parts.

The form of the invention here particularly described and illustrated in the drawings is presented merely to indicate how the invention may be applied. Other forms, embodiments and applications of the invention which come within the proper scope of the appended claims will, of course, suggest themselves to those skilled in the knitting machine art.

I claim:

1. 1n 3, knitting machine, a shaft upon which knitted fabric is rolled, and means for rotating said shaft responsive to the tension of the knitted fabric being rolled, said means comprising a driving gear concentrically fixed upon said shaft, a pulley mounted for free rotation upon said shaft, a belt for continuously rotating said pulley, and a planetary gear journaled in said pulley meshing with said driving gear, in combination with an idler gear having more teeth than said driving gear concentrically mounted on said shaft in mesh with said planetary gear, a lever system in contact with the fabric as it approaches the roll, and a brake operated by said lever system to fix said idler gear with respect to the knitting machine and thus rotate said planetary gear, said driving gear and said shaft.

2. In a knitting machine, a shaft upon which knitted fabric is rolled, a pulley for rotating said shaft to roll the knitted fabric thereon, a belt for constantly rotating said pulley, and a friction clutch for engaging said shaft and said pulley, in combination with means responsive to the tension of the fabric being wound for actuating said clutch, said means comprising a feeler bar over which the fabric passes before being rolled, a pivoted lever supporting said feeler bar at one end thereon, a counterweight at the other end of said lever for overbalancing the weight of said fabric being rolled thereon, said means comprising a driving gear fixed to said shaft concentrically therewith, an idler plate mounted upon said shaft for free rotation thereon, an idler gear concentrically connected to said idler plate for rotation therewith upon said shaft, the number of teeth upon said idler gear being greater than the number of teeth upon said driving gear, apulley mounted for free rotation on said shaft, a belt for rotating said pulley, a planetary gear journaled for rotation between the hub and the rim of said pulley, said planetary gear being in mesh with both said driving gear and said idler gear, and a fixed plate having a central opening therein through which said shaft extends disposed closely adjacent to said idler plate, in combination with friction means for simultaneously engaging said idler plate and said fixed plate, a clutch lever for operating said friction means, and a lever system responsive to the tension of the fabric being wound connected to said clutch lever to limit idling of said idler plate and cause said planetary gear to rotate about said idler gear and rotate said driving gear and said shaft.

4. In a knitting machine, a shaft upon which knitted fabric is rolled, and means for rotating said shaft responsive to the tension of the knitted fabric being rolled thereon, said means comprising a driving gear fixed to said shaft concentrically therewith, a circumferentially flanged idler plate mounted upon said shaft for free rotation thereon, an idler gear concentrically connected to said idler plate for rotation therewith upon said shaft, the number of teeth upon said idler gear being greater than the number of teeth upon said driving gear, a pulley mounted for free rotation on said shaft, a belt for constantly rotating said pulley, a planetary gear journaled for free rotation between the hub and the rim of said pulley, said planetary gear being in mesh with both said driving gear and said idler gear, and a circumferentially flanged plate having a central opening therein through which said shaft extends, said iianged plate being fixed against rotation with its flange surrounding that of said idler plate, in combination with a brake band having one end fixed to the flange of said fixed plate extending inside the flange of said fixed plate surrounding the flange of said idler plate, a clutch lever connected to the other end of said brake band, and a lever system responsive to the tension of the fabric being wound connected to said clutch lever for tightening said brake band to limit idling of said idler plate and to cause said planetary gear to rotate said driving gear and said shaft.

5. In a knitting machine, a shaft upon'which knitted fabric is rolled, and means for rotating said shaft responsive to the tension of the knitted fabric being rolled thereon, said means comprising a driving gear fixed to said shaft concentrically therewith, a circumferentially flanged idler plate mounted upon said shaft for free rotation thereon, an idler gear concentrically connected to said idler plate for rotation therewith upon said shaft, the number of teeth upon said idler gear being one greater than the number of teeth upon said driving gear, a pulley mounted for free rotation on said shaft, a belt for constantly rotating said pulley, a planetary gear journaled for free rotation between the hub and the rim of said pulley, said planetary gear being in mesh with both said driving gear and said idler gear, and a circumferentially flanged plate having a central opening therein through which said shaft extends, said plate being fixed to the frame of the knitting machine with its flange surround ing that of said idler plate, in combination with a brake band having one end fixed to the flange of said fixed plate extending inside the flange of said fixed plate surrounding the flange of said idler plate, a clutch lever pivoted to said fixed plate and connected to the other end of said brake band, and a weighted lever system responsive to the tension of the fabric being wound connected to said clutch lever for tightening said brake band to limit idling of said idler plate and said idler gear, whereby said planetary gear rotates about said idler gear to turn said driving gear and rotate said shaft.

6. For use in rotating a knitting machine shaft upon which knitted fabric is rolled up, a clutch comprising a planetary gear train for rotating the shaft, driving means for the gear train and a brake band for applying friction to an element of said train, whereby the shaft is driven at lesser speed than the gear train driving means in response to the degree of friction applied.

7. For use in rotating a knitting machine shaft upon which knitted fabric is rolled up, a constantly driven pulley, in combination with a clutch comprising a planetary gear train for rotating the shaft, and a brake band for applying friction to an element of said train, whereby the shaft is driven by said pulley at a speed reduced in comparison to the speed of the pulley and responsive to the degree of friction applied.

8. In the combination of parts of claim 7, the provision of a lever system actuated by the tension of the fabric adapted to control the degree of friction applied to said element in the gear train in such manner that the speed of the roll reduces progressively to synchronism with the knitting as the rolling up of the fabric catches up with the knitting.

9. A shaft on which fabric is rolled up on a knitting machine, and a lever system actuated by the tension of the fabric, in combination with a speed reduction gear train in driving relation to the shaft, and friction coupling means in the gear train controlled by the lever system, said speed reduction gear train being adapted to supply gradnally the changes in speed demanded by the lever system, whereby the fabric tension is adjusted gradually.

10. In the combination of parts of claim 9, the provision of a hunting tooth gear in the gear train which limits the maximum speed of rotation of the shaft.

11. In the combination of parts of claim 9, an idler gear and a friction clutch in the train, the latter being adapted to adjust the rate of drive by the train by applying force to the idler gear.

12. In the combination of parts of claim 9, the use of planetary gears in the speed reduction train, in combination with a friction clutch in the train to restrain the planetary action of the gear train, whereby a speed of rotation of the shaft corresponding to the knitting is obtained.

13. In the combination of parts of claim 12, the provision of a hunting tooth gear in the gear train whereby the speed of the shaft can be kept in constant correspondence with the tension of the fabric but always gradual in its action.

ROBERT H. LAWSON.

REFERENCES CITED The following references are of record in the 

